The present invention is in the field of clothing manufacture, more particularly relating to the automated assembly of garments.
Garments have long been made by joining two or more panels of limp fabric, forming seams, so that the composite surface of the joined panels establishes a desired three-dimensional contour. Typically, the design process for a garment includes the step of segmentation of the desired finished contour into planar patterns having shapes corresponding to panels for the garment. These patterns are used to generate the panels which may be cut from a portion of a limp fabric. The panels are then joined at their edges (by manual or machine sewing) to form the finished garment. For automated garment assembly, it is preferable that the design permits the joining operation to be performed in a plane. In most cases, however, in the prior art, the seam joining for a garment requires three dimensional positioning of the joining stitches. As a result, such seam joining is generally accomplished manually.
Thus, to manufacture a garment using planar patterns, the patterns are used to define the contours of panels on a portion of fabric, and the panels are then cut from that portion. Thereafter, the cut panels are joined to form the garment. In order to efficiently produce large numbers of garments, for example in commercial production, the panels may be cut from elongated strips of fabric extending from bolts of fabric. Various computer controlled systems have been developed in the prior art to accomplish garment production from such bolts of fabric. For example, there are known systems for automatically laying out panels, accommodating a full range of garment sizes, on a strip of material from a bolt which maximizes fabric utilization (i.e., minimizes waste). There are also computer controlled cutting systems, for example using reciprocating knives, which accurately and quickly cut panels from a large number of strips at one time. Further, there are systems which can automatically position the cut panels so that certain of their edges-to-be-joined may be joined by sewing, or fusing, under the control of a computer.
One of the principle limitations of the prior art clothing assembly techniques is that most automatic, or computer controlled, joining systems can only effectively perform panel edge joining in a flat plane, i.e., the seam must lie in a plane. Since many garments include seams which may be formed in a flat plane, automated systems have been very effective in enabling the efficient production of garments or other articles. For example, U.S. Pat. No. 3,699,591 shows a system for manufacturing simple garments which include only flat plane seams which may readily be performed by known systems. Similarly, U.S. Pat. No. 4,462,118 shows a method for assembling pants from two substantially identical fabric panels using flat plane seams for joining two panels.
However, most garments must be assembled with at least some seams which are not flat plane seams, i.e., the garment design includes seams which cannot be formed in a plane. By way of example, a pair of pants might be formed from two panels which are joined with an inseam and crotch seam intersecting at a saddle region, with the inseam extending between the lowermost portions of the leg portions of the pants and the crotch seam extending between two points on the top of the pants. Using conventional assembly techniques for such pants, one of these seams is first formed in its entirety and then the other is formed using other than automated flat plane sewing techniques. In order to assemble such garments in the prior art, these non-flat plane seams cannot be formed using known automated seam-joining systems, but rather must be formed either by hand or, more typically, human operator-controlled feeding of the panels to a sewing machine (or other type of machine) head. Consequently, the labor cost is relatively high compared to that encountered for a garment which might be assembled entirely by a computer system.
However, U.S. Pat. No. 4,462,118, assigned to the assignee of this application, discloses a method for forming pants having such intersecting crotch and inseams where all seam joining is performed in a flat plane. One requirement for that method is that the cross-seams be mutually aligned prior to completion of the inseam. While this step is easily performed with human intervention, there are no known automated mechanisms which can perform this step. With such a mechanism, fully automated assembly of pants could readily be performed.
Accordingly, it is an object of the present invention to provide an improved apparatus of garment manufacture.
It is yet another object of the invention to provide an apparatus for aligning cross-seams during the assembly of articles using flat plane seam joining techniques.